The present invention relates to refrigeration systems.
There has previously been disclosed in U.S. Pat. No. 3,933,004 a refrigeration system for a chamber including a compressor, a condenser and an evaporator, forming a cooling circuit, and having a hot gas by-pass conduit from the compressor to the evaporator, in which is provided means for apportioning the flow of compressed refrigerant gas from the compressor between the condenser and the by-pass conduit to provide, during a temperature controlling phase of refrigeration, gas flows through both the condenser and the by-pass conduit, the apportioning means being arranged to control the relative proportions of the gas flows through the condenser and the by-pass conduit to provide either net heating or net cooling of the chamber.